Werkzeugeinspannvorrichtung für eine Oberfräse

摘要

A bit attaching arrangement (12) for a power tool (10) includes a bit locking member rotatable with respect to the output shaft (18) of the power tool. A first gear (48) is fixed to the bit locking member (40) so that rotation of the first gear causes rotation of the locking member. A second gear (60) is fixed to the output shaft (18) so that rotation of the second gear causes rotation of the output shaft (18). A third gear (74) engages both said first and second gear simultaneously and is capable of rotation by an operator of the power tool. Rotation of the third gear results in counter rotation between the bit locking member and the output shaft so as to result in securement of the bit (26) to the shaft. A further aspect of the invention includes a pinion shaft (76) onto which the third gear (74) is mounted. The pinion shaft (76) is slidably mounted to the power tool so that the third gear may be moved between a position where it engages both the first and second gears and can be used to tighten the bit in place, and a second position wherein it does not engage either of the gears and allows operation of the power tool.